comparing fuel performance 2014 Cobalt R5 vs 2012 323

[theC3xplorer]

I'm considering switching from my 2014 Cobalt R5 with a Volvo Penta 380 to a 2012 Cobalt 323 with twin VP 8.1 400 HP engines. How well they perform on fuel intrigues me. Does anyone have data or experience comparing the fuel efficiency of these two configurations? Any advice on how to measure and compare, or what to anticipate?

 

[GalaxyObsession]

The 2012 Cobalt 323 will be less fuel efficient than the 2014 Cobalt R5 and you should see a difference in a few mpgs. If you're strictly after the more fuel efficient one, stick with the R5. If you're after power, space and comfort, the 323 is a better option

 

[CobaltAdventurer]

Appreciate the info, thats incredibly helpful! What kind of difference do you usually notice on the water between the two? Is it just a few miles per gallon or is it more obvious?